The overarching theme of this proposal is Impact of Tumor Heterogeneity on Cancer Progression. The Experimental Component is therefore geared to quantifying cancer cell heterogeneity with respect to hallmark traits of cancer progression, such as proliferation, metabolism and motility. We will quantify this trait heterogeneity in model cultured cell lines, under several mE perturbation, as average and distribution measurements performed at the single-cell level by high-content automated microscopy and image processing. Trait distributions will also be resolved as statistical subpopulations, in order to uncover common trends between cell lines. Several In vivo tumor experimental systems will complement in vitro assays for the purpose of theoretical model validation. We have assembled a team of talented experimentalists that cover all specific skills needed for this Component, as shown by their distinguished publication records. Staff scientists will assure continuity of Component technology.